This invention relates to a nail-removing hammer which has at least one nail-removing means in addition to a conventional rearwardly extending claw. A claw comprising a rearwardly opening V-shaped slot located at the upper rear portion of the hammer poll provides an excellent mechanical advantage for removing, or starting to remove, heavy nails. An additional nail-removing claw located in a forward throat portion of the hammer head can be used to complete the removal of long nails. In a preferred embodiment, the claw consists of a downwardly opening V-shaped slot.
Most commonly available hammers have a nail-removing claw located at a rear portion of the hammer body or head. Standard carpenter's hammers include rip-claw or straight-claw hammers, generally used for framing type work, and curved-claw hammers, which are used for finish work. A well-cnown problem with the standard straight-claw hammer is its inability to remove long nails easily or quickly; once the nail is removed in the forked claw to a distance of about one inch, leverage is lost, and the hammer head actually becomes the fulcrum for further removal. As the head rolls over, leverage is lost, and the nail bends at an extreme angle instead of being removed. This is a particular problem when removing larger nails, e.g., in the 6d-16d size.
In addition, hammers having standard claws are generally limited in mechanical advantage for pulling nails. Nails which are particularly difficult to remove, such as large nails, glue-coated nails, or nails having ribbed shanks, are particularly problematic for conventional clawed hammers because the nail is located at a relatively long distance from the fulcrum of rotation, thereby requiring a very large rotational force to begin the nail removal process. With the top claw of the hammer of the invention, a much improved mechanical advantage is obtained for removing nails of this sort. In addition, conventional hammers have difficulty removing nails having heads which are embedded well into the surface into which they are driven, because the claw tips are relatively blunt and difficult to wedge under the embedded head. In such cases, a separate tool known as a "cat's paw" is used to drive underneath the embedded nail head to begin the removal process. The top claw on the hammer of the invention is fashioned in such a manner as to be useful as a cat's paw, with the claw edges being relatively easy to drive underneath a nail head.
Other problems with conventional hammer claws relate to the removal of relatively long nails, or nails which have already been partially removed from the wood. When driving nails, weaker nails such as galvanized nails tend to bend, especially when being driven into hard woods or near a knot in the wood; the bent nails must of course be immediately removed. Long nails are used in the assembly of scaffolding, bleachers, concrete form work, and the like, and must be removed upon disassembly. For this type of nail removal, it is often necessary for a carpenter to use a special nail-pulling tool in addition to the hammer, or to find a block of wood or other object to place underneath the head of the hammer to raise the fulcrum point above the wood surface for greater leverage. This latter method is somewhat inefficient, and sometimes results in instability, with the hammer handle pulling off to one side. Nails driven in tight areas, or driven on a slant, glue-coated nails, and ribbed nails present additional difficulties. These problems can cause frustration and lost time if a carpenter needs to descend from a ladder or scaffold to search for a wrecking bar or piece of wood to use in removing a recalcitrant nail.
The problem of removing long nails with standard-claw hammers has been recognized for many years. One approach to solving the problem is to have a movable able arm which extends outwardly from the top of the hammer and which can act as a fulcrum (thus replacing the block of wood) when pulling long nails. Examples of tools having this capability are shown in Thayer, U.S. Pat. No. 35,715, Shepard, U.S. Pat. No. 587,242, Palmer U.S. Pat. No. 856.097, Frey, U.S. Pat. No. 1,125,999, Eveleth, U.S. Pat. No. 540,967, and Rairden, U.S. Pat. No. 1,132,879. While these devices provide additional leverage for removing long nails, the requirement of having moving parts generally makes the hammers somewhat more expensive and less durable. In addition, each time a long nail must be removed, the hammer must be adjusted to provide for the extended fulcrum.
It is also known to incorporate various types of nail-extracting devices in addition to or in replacement of a standard claw for hammers or similar hand tools. For example, in David, U.S. Pat. No. 3,150,858, a straight-claw hammer having two additional claws with openings circumferential to the hammer head is disclosed. The nail is removed by engaging the head in the claw and rotating the hammer about the axis of the hammer head, in effect wrapping the nail around the hammer body. Additional torque must be applied by hand since the fulcrum is off-center to the handle. Furthermore, this device is not adapted to remove nails in tight places. Similar devices showing claws which engage the nail and are rotated about the body axis to remove the nail are found in Darr et al, U.S. Pat. No. 1,600,275, and Chase, U.S. Pat. No. 516,644. In Thorson, U.S. Pat. No. 1,656,652, Darr et al, U.S. Pat. No. 1,600,275, and Andersen, U.S. Pat. No. 1,713,810, tools are disclosed having notches in side portions of conventional hammer claws which are used to engage nails for removal. Both of these tools are used in the standard manner, i.e., rotation of handle over head, as is experienced with a conventional claw hammer. A further unusual claw design including a plurality of transverse slots in a rearwardly extending claw member is disclosed in Connor, U.S. Pat. No. 3,963,215.
A need exists for a hammer which has no moving parts and which can easily and quickly extract long nails. Furthermore, a need exists for a claw design in which the nail-removing surface rests directly under the head of a nail, simultaneously exerting upward force on the shaft and entire underface of the nail head, thus reducing the chances of the nail head bending or popping off. In accordance with the invention, a hammer is provided which can pull almost any size nail, including "duplex" or "scaffold" nails without the need for separate tools. With the hammer of the invention, there is no need for the use of a crowbar or a block of wood for additional leverage.
Furthermore, there is a need for a nail-holding hammer which can grip a nail prior to the nail being hammered into place. In many instances, a carpenter will find himself elevated on a ladder or scaffolding, with a need to use one hand to provide leverage, to maintain balance, or to hold on to a stationary object for his own safety. Ordinarily, a user will hold the nail with one hand and the hammer with the other hand, striking the nail a first blow while the nail is being held in the other hand. If the nail could be held by the hammer for the first blow, it would permit use of the other hand for safety purposes. Furthermore, the ladder or scaffold could be moved less frequently, since the carpenter would be able to reach father from the support to drive nails. The hammer of the invention provides these advantages.
Accordingly, it is an object of the present invention to provide a hammer for the rapid and easy extraction of long nails. It is a further object of the invention to provide a versatile tool having no moving parts and having a plurality of nail-extraction means for nails of different lengths and different difficulties of removal. It is yet a further object of the invention to provide a claw hammer which provides substantially greater leverage than conventional hammers for removal of long nails. It is another object of the invention to provide a hammer having a nail extracting claw which is also useful to hold a nail prior to, and during the initial impact of insertion of the nail into an object. These and other objects of the invention are provided by the nail-driving and nail-extracting device disclosed herein.